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From:   David Howells <dhowells@redhat.com>
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To:     Bruce Fields <bfields@fieldses.org>
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Subject: Re: Why the auxiliary cipher in gss_krb5_crypto.c?
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Date:   Fri, 04 Dec 2020 16:01:53 +0000
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Bruce Fields <bfields@fieldses.org> wrote:

> > Reading up on CTS, I'm guessing the reason it's like this is that CTS =
is the
> > same as the non-CTS, except for the last two blocks, but the non-CTS o=
ne is
> > more efficient.
> =

> CTS is cipher-text stealing, isn't it?  I think it was Kevin Coffman
> that did that, and I don't remember the history.  I thought it was
> required by some spec or peer implementation (maybe Windows?) but I
> really don't remember.  It may predate git.  I'll dig around and see
> what I can find.

rfc3961 and rfc3962 specify CTS-CBC with AES.

David